Phase II Study of Avastin + Erbitux + Irinotecan as 2nd Line Treatment of Colorectal Cancer

Inclusion Criteria: * Histologically confirmed locally advanced or metastatic colorectal cancer. * Measurable or evaluable disease according to the Response Evaluation Criteria in Solid Tumors (RECIST) * ECOG performance status ≤ 2 * Age 18 - 72 years * Patients with de novo refractory disease (progression of disease as best response at 1st line therapy with FOLFOX/Avastin) * Adequate liver (Bilirubin ≤ 1.5 UNL, SGOT/SGPT ≤ 4 UNL, ALP ≤ 2.5 UNL),renal (Creatinine ≤ 1.5 UNL) and bone marrow (ANC ≥ 1,500/mm3, PLT ≥100,000/mm3) function * Patients must be able to understand the nature of this study * Written informed consent Exclusion Criteria: * History of serious cardiac disease (unstable angina, congestive heart failure, uncontrolled cardiac arrhythmias). * History of myocardial infarction or stroke within 6 months. * Clinically significant peripheral vascular disease. * History of abdominal fistula, gastrointestinal perforation or intraabdominal abscess within 28 days prior to Day 0. * Presence of central nervous system or brain mets. * Evidence of bleeding diathesis or coagulopathy. * Patients with known hypersensitive reaction to cetuximab * Blood pressure \> 150/100 mmHg. * Pregnant or lactating woman. * Life expectancy \< 3 months. * Previous radiotherapy within the last 4 weeks or \> 25% of bone marrow. * Metastatic infiltration of the liver \>50%. * Patients with chronic diarrhea (at least for 3 months) or partial bowel obstruction or total colectomy. * Active infection requiring antibiotics on Day 1. * Second primary malignancy, except for non-melanoma skin cancer and in situ cervical cancer. * Psychiatric illness or social situation that would preclude study compliance.